Grinder pump

ABSTRACT

The grinder pump includes an electric motor drive, cooperating cutter blade and grinder members one of which is secured to the motor shaft at an inlet for the grinder pump unit, an axial flow inducer impeller axially inwardly of and immediately adjacent to the cooperating cutter blade and grinder members, and a centrifugal pump means having an inlet directly connecting to and receiving the discharge from the axial flow inducer impeller, all of the driven members being controlled by and carried on the shaft of the electric motor.

United States Patent Conery et a1.

[ 51 Mar. 21, 1972 [54] GRINDER PUMP [72] Inventors: William J. Conery;Donald A. Kaessen,

both of Ashland, Ohio 1 [73] Assignee: Hydr-O-Matic Pump Company,Hayesyi LeQhiQ. [22] Filed: Apr. 1, 1971 211 App]. No.: 130,276

[52] U.S.Cl. ..24l/46.11, 241/257 G, 241/258 [51] Int. Cl. ..B02c 18/40[58] Field ofSearch ..241/46 A, 46 B, 46.11,46.l7, 241/257 R, 257 G,258, DIG. 32

[56] References Cited UNITED STATES PATENTS 2,714,045 7/1955 Simenson..241/D1G. 32

2,853,249 9/1958 Wilder ..241/46.1l X 2,857,109 10/1958 Haeussler....24l/46.1l 3,128,051 4/1964 Smith ..241/46.l1

Primary ExaminerGranville Y. Custer, Jr. Attorney-Oldham & Oldham [57]ABSTRACT The grinder pump includes an electric motor drive, cooperatingcutter blade and grinder members one of which is secured to the motorshaft at an inlet for the grinder pump unit, an axial flow inducerimpeller axially inwardly of and immediately adjacent to the cooperatingcutter blade and grinder members, and a centrifugal pump means having aninlet directly connecting to and receiving the discharge from the axialflow inducer impeller, all of the driven members being controlled by andcarried on the shaft of the electric motor.

11 Claims, 11 Drawing Figures PATENTEUMARZ] m2 SHEET 1 [1F 2 INVENTORSWILLIAM J. CON ERY BY DQNALD A. KAESSEN FIG.I

ATTORNEYS.

PATENTEDHARZI I972 SHEET 2 BF 2 FIG. IO

INVENTORS. WILLIAM J. CQNERY DONALD A. KAESSEN ATTORNEYS.

GRINDER PUMP The present invention, in general, relates to a grinderpump unit having improved characteristics for pumping liquids, andcutting up solids in the volume of liquid being processed.

BACKGROUND OF THE INVENTION Heretofore there have been various types ofgarbage grinders and other types of grinders wherein a driven rotatablecutter means is provided for breaking up solids and for forcing ormoving a fluid or a liquid through the grinder unit. Some of thesegrinder units have been conventional garbage grinders or disposals asshown in US. Pat. No. 2,682,356, while other patented structures in theprior art have provided a double cutting or grinding action where afterthe material has passed through an initial inlet break-up and grindingor cutting zone, following grinding or cutting action is provided in theunit, as evidenced by the constructions shown in U.S. Pat. Nos.2,853,249; 2,442,812; and 2,322,058. However, even in these multiple ordouble cutting units, it has been difficult to provide a grinder ordisposer unit wherein substantially any solid material can be introducedinto the device and be ground up into satisfactory small elements forflow through the grinder or disposal system, It furthermore has beencustomary in most instances for these grinder units to be located onvertical axes with some discharge means at the lower portion of theunit, and relatively small volumes of liquid are processed per minute.

In Wilder US. Pat. No. 2,853,249, the suggestion of having some type ofpump impeller blades in the unit is proposed, but these blades areintegral with the shearing or grinding member in the unit and a veryinefficient pumping action is secured.

The general object of the present invention is to provide a novel andimproved pumpgrinder means which includes a separate pump to aid indrawing pumped liquids through the grinder unit of the invention at adesirable fast volume flow rate.

A further object of the invention is to provide improved grinder and/orcutting actions in the grinder unit; and to provide an axial flowinducer impeller which cooperates with the initial grinding or cuttingsection of the unit for additional cutting action and a drawing orforcing of the pumped liquid axially in the unit, and a centrifugal pumpconnected to and receiving the discharge from the axial flow inducerimpeller for pumping it out of the unit.

Another object of the invention is to provide an improved associationbetween an inlet rotating cutter blade and an associated stationarygrinder ring means having a plurality of cutting and/or grinding teethprovided thereon and wherein alternate teeth in the grinder ring are ofdifferent radial lengths to improve the cutting action and axial flow ofa liquidsolid mixture through the apparatus of the invention.

Another object of the invention is to provide a grinder pump unit whichis adapted to process large volumes of sewage or other materials such asliquids having solids therein and including rags, garbage and othermaterials and wherein the grinder pump unit will break up the solidsinto small pieces for flow through the apparatus of the invention forprocessing large volumes of sewage or other materials rapidly andefficiently.

Further objects of the invention are to provide an improved grinder ringtooth assembly for use in association with a driven cutter blade at theinlet of the unit and for improved volume flow of materials through theapparatus with a minimum of vibration to the rotating cutter blade; toprovide sizable passages for fluids in the initial cutting or grindingzone of the unit; to provide an improved secondary cutting action in agrinder pump assembly by a disc type of an axial flow inducer impellerlocated axially immediately adjacent the stationary grinder ring for asecondary cutting action between the initial cutting members and theaxial flow inducer impeller in the apparatus; to provide an axial flowinducer impeller wherein the teeth thereon extend the full axial lengthof the impeller whereby the impeller can be turned over, after removalfrom the apparatus, and be replaced to provide a double cutting life forthe impeller before requiring sharpening; to provide improvedcooperation between the teeth on an axial flow inducer impeller andassociated inlet cutting or grinding means in the apparatus, to providean odd number of cutting teeth on the inlet grinder ring and withalternate teeth being a different radial length; to provide a grinderpump with a submersible electric motor so that the complete unit can besubmerged in the pumped liquid; to provide the submersible motor withtwo seals having an oil chamber between the seals to avoid contaminationof the motor with the pump material; to provide an improved bearing inthe seal oil chamber directly adjacent to the initial impeller seal inthe unit; to provide a grinder pump that can be used to force materialaxially therethrough in any desired position and to provide asubmersible grinder pump which can be used in a sewage or otherrefuse-liquid receiving sump to force large volumes of material into adischarge system connected to the sump.

Reference now is made to the associated drawings wherein:

FIG. 1 is a vertical section through the grinder pump embodying theprinciples of the invention and diagrammatically showing such grinderpump positioned in a sump;

FIG. 2 is a fragmentary inlet end elevation of the grinder pump of FIG.1;

FIG. 3 is a vertical section of the grinder ring means of FIG.

FIG. 4 is a fragmentary elevation of the stationary grinder ring of theapparatus of FIG. 1;

FIG. 5 is an end elevation, partially in vertical section, of thestationary grinder ring of FIG. 4;

FIG. 6 is a fragmentary elevation of the cutter ring blade of theapparatus;

FIG. 7 is a side elevation of the cutter ring of FIG. 6;

FIG. 8 is a fragmentary plan of the axial flow inducer impeller of theapparatus;

FIG. 9 is an elevation of the impeller of FIG. 8 taken on line 9-9;

FIG. 10 is a vertical section through the pump impeller of thecentrifugal pump in the grinder pump; and

FIG. 11 is a fragmentary plan view of a portion of the impeller of FIG.10 taken on line ll-l1.

When referring to corresponding members shown in the drawings andreferred to in the specification, corresponding numerals are used tofacilitate comparison therebetween.

INVENTIVE SUBJECT MATTER In general, the present invention as oneembodiment thereof, relates to a grinder pump unit adapted for forcedflow of sewage or other material therethrough and wherein a housing andelectric motor means is present and includes a shaft extending from themotor, the housing having an inlet provided therefor and cooperatingcutter blade and grinder means members are positioned at the inlet forthe unit with the cutter blade member being secured to the shaft, anaxial flow inducer impeller is secured to the shaft axially inwardlyimmediately adjacent the cutter blade member, and a centrifugal pumpmeans is provided within the housing and includes an impeller secured tothe shaft. The pump has an inlet directly connecting to and receivingthe discharge from the axial flow inducer impeller, and a dischargemeans is provided for the pump and connects thereto.

Reference now is particularly directed to the details of the structureshown in the drawings, and a grinder pump is indicated as a whole by thenumeral 10. This grinder pump includes a housing indicated as a whole bythe numeral 12 with a suitable electric motor 14 being provided in oneportion of the housing 12 which is shown made from several axiallyabutting sections. The electric motor 14 has a shaft 16 which protrudestherefrom and extends substantially to an inlet 18 provided at one endof the housing 12. This inlet 18 is formed in an inlet ring 20 that issecured to a section 22 of the housing 12 as by cap screws 24 or thelike. The inlet ring preferably has a pinrality of cutting or grinderteeth 26 formed therein and extending generally axially thereof.

The axially outer end of the motor shaft 16 has an inlet cutter blademember or rotor 28 secured thereto, and such cutter or grinder disc ormember 28 has at least a pair of axially outwardly extending cutterblades 30 and 32 formed thereon or usually formed integrally therewithand terminating in axially directed outer edges 34 at the periphery ofthe disc as best shown in FIGS. 6 and 7 of the drawings. Any othersuitable or conventional cutter or grinder means including smaller teeth36 are provided on the axially outer face of the disc 28 for additionalcutting, grinding or shredding action on materials being introduced intoor flowing through the grinder pump of the invention.

The initial or primary grinding and/or cutting action is obtained in thegrinder pump by cooperation of the disc 28 and the teeth thereon with afixedly positioned grinder ring, means or member 38 that is of annularform and is suitably seated in a recess provided in the housing section22 and secured thereto in any conventional manner. This grinder member38 is of annular form and is shown in detail in FIGS. 4 and of thedrawings which indicate that a plurality of grinder teeth 40 areprovided at circumferentially spaced radially inner portions of thegrinder member 38 and with, preferably, a circumferentially outwardlycurved recess 41 being provided intermediate each pair of the grinderteeth 40. FIG. 4 of the drawings best shows, as a further feature of theinvention, that an odd number of grinder teeth 40 are provided in thegrinder ring 38 and with alternate ones of these teeth as indicated at400 and 40b being of different radial length, as indicated by thedifferent lengths of the lines 11-6 and a-d in FIG. 4. For this pairedrelationship of alternately longer and shorter teeth to form a ring withan off number of teeth therein, one pair of adjacent teeth have the sameradial length and in this instance, the tooth 400 is shown to be of thesame length as its adjacent tooth 40a and where the spacing of thistooth from the center of the ring is indicated by the line a-d, which isof the same length as the line a-c. Thus, by this feature of theinvention, a relatively large pathway is provided by the recesses 41 inthe grinder ring 38 whereby the material being pumped can rapidly flowin volume through the operating grinder and/or cutting zone or assemblyformed by the cutter or grinder disc 28 in association with the grinderring 38 that encompasses the grinder disc. The circumferentially spacedaxially extending cutting edges of the grinder teeth 40 are immediatelyadjacent and parallel to the straight edges 34 on the axially extendingcutter blades 30 and 32 on the cutter disc 28 for effective cutting andgrinding action by driven rotation of the shaft 16.

As a further important feature in the grinder pump unit of theinvention, an axial flow inducer impeller 42 is positioned immediatelyadjacent to the grinder disc 28 on the axially inner surface thereof andwhich impeller 42 is of generally disc shape. This axial flow inducerimpeller has a plurality of blades or teeth 44 provided thereon whichteeth 44 have an appreciably inclination, as shown in FIG. 9, to thelongitudinal axis of the grinder pump and which teeth likewise extendsome appreciable circumferential distance around the periphery of theimpeller 42. In the present instance, only four of these teeth 44 areshown and they are circumferentially spaced from each other and with theends of each of the teeth 44 terminating flush with an edge surface ofthe impeller as indicated at 44a and 44b of the drawings. This impeller42 is suitably secured to the shaft 16 for drive thereby, and it shouldbe noted that the axially outer edges 44a of the teeth 44 are positionedimmediately adjacent and below the axially inner edges or ends of theindividual teeth 40 provided on the grinder ring 38 whereby any elongateor fibrous members passing into the grinder pump have a secondarycutting or shredding action effected thereon by the relative rotation ofthe impeller 42 in relation to the grinder ring 38 and the teeththereon.

Yet a further important feature of the invention is that a centrifugalpump is formed as a unit with the remaining portions of the apparatusand which unit includes an impeller 46 suitably secured to and carriedby the motor shaft 16 for drive thereof as a unit with the grinder disc28 and associated means. This impeller 46 is a portion ofa centrifugalpump 48 that forms an enclosure around the impeller 46 by a portion ofthe housing section 22 that forms a pumping chamber 50 around theperiphery of the impeller 46. The impeller 46 may have any suitablecircumferentially pumping vanes indicated at 52 provided on the facethereof adjacent to the inlet 53 for the pump 48. Such inlet 53 isdirectly axially associated with and positioned immediately adjacent thedischarge face or surface of the impeller 42. The inlet is annular andis aligned with the axial flow of the pumped liquid provided by theaxial flow inducer impeller 42. A conventional outlet 54 is formed in aportion of the housing means 12 and an outlet pipe 56 connects theretofor discharge of the pumped material.

By this combination of an initial cutting and grinding action on thepumped material, plus a secondary cutting action between the axial flowinducer impeller and the grinder ring teeth, an effective cutting and/orshredding action is provided on the solids in the pumped liquid, and byuse of a centrifugal pump directly connected to and receiving the outletfrom the axial flow inducer impeller 42 and associated means, a positiveflow of pumped liquid and materials can be obtained through the grinderpump of the invention. At the same time, any solid materials initiallypresent in this liquid can be cut or ground up to small particle formwhereby rags and other fibrous materials can pass through the grinderpump and be effectively processed to be moved on in the liquid treatmentsystem for further action on the pumped fluid.

As yet a further feature of the invention, it is preferred that asubmersible type of an electric motor 14 be used in the grinder pump sothat the grinder pump can be positioned in a known manner as showndiagrammatically in FIG. 1, in a sump 60. The grinder pump 10 can bepositioned in such sump in any conventional manner as being supported onthe bottom of the sump by suitable leg or bracket means, or the unit canbe positioned on a vertically extending support means of a known type.In this instance, the inlet 18 faces downwardly of the sump but isspaced from the bottom thereof and the liquid in the sump can rise abovethe motor 14. Conventional controls would be provided for the motor todrive it upon predetermined depth of liquid received in the sump and forcontrolling motor drive until a predetermined lower liquid level isobtained in the sump.

For this electric motor 14 to be effectively used in the practice of theinvention, it is important to separate the motor from the pumpedmaterial and thus in the present invention, a pair of axially spacedseal assemblies have been positioned in engagement with the motor shaft16. These seal assemblies are indicated as a whole by the numbers 62 and64. A separate housing section 66 is provided as a portion of thehousing means 12 and is suitably attached thereto with the section 66providing a chamber 68 between the seal 62 and 64. Thus, a suitablematerial, such as oil, can be received in the chamber 68 and this formsan isolation chamber between the electric motor and the pumped liquid.It also is necessary to provide a bearing 70 that is carried by aseparate end plate 72 formed as a portion of the casing of the pump 48and which has a tubular extension 72a extending therefrom in which thebearing 70 for the shaft is received to aid in positioning this shaftfor efficient, maintenance free operation.

The seals 62 and 64 can be of any known mechanical type.

The provision of the axially spaced seals 62 and 64 with an oil chambertherebetween aids in the use of the invention with a submersibleelectric motor that can be adapted for upward pumping of liquidmaterials while grinding, shredding and cutting any solids present insuch materials.

It should be noted that the axial flow inducer impeller 42 is of a flatdisc shape and that the blades or teeth 44 formed thereon can beserviceable with rotation of the impeller in opposite directions. Thus,the impeller disc can be removed from the unit of the invention, beturned over and be replaced for further pumping action. This gives adouble life on the impeller 42 without any sharpening action beingprovided or required, so as to reduce maintenance and operation costs ofthe unit of the invention.

The unit of the invention has provided a high rate or volume of forcedflow of materials from the grinder pump and at the same time solids insuch pumped liquid have been cut or ground to suitable form for passagethrough the apparatus of the invention. Thus, it is believed that theobjects of the invention have been achieved.

While one complete embodiment of the invention has been disclosedherein, it will be appreciated that modification of this particularembodiment of the invention may be resorted to without departing fromthe scope of the invention as defined in the appended claims.

What is claimed is:

l. A grinder pump comprising an electric motor means including a shaftextending therefrom, an inlet being provided for said housing,cooperating cutter blade and grinder means members one of which issecured to said shaft at an inlet for the unit, an axial flow inducerimpeller positioned axially inwardly of and immediately adjacent saidcutter blade member, said impeller being secured to said shaft, and acentrifugal pump means including an impeller secured to said shaft, saidpump having an inlet directly connecting to and receiving the dischargefrom said axial flow inducer impeller.

2. A grinder pump unit as in claim 1 where teeth are provided on saidgrinder means and some teeth are longer than others.

3. A grinder pump as in claim 1 where said grinder means has an oddnumber of teeth therein and every other one ofsaid teeth is radiallyshorter than the teeth adjacent thereto, except for one pair of adjacentteeth which are of the same length.

, 4. A grinder pump unit as in claim 1 where said axial flow inducerimpeller has teeth thereon extending the axial length thereof andsurfaces of said teeth cooperate with surfaces of said grinder teeth foradditional cutting and/or grinding action.

5. A grinder pump unit comprising a housing and electric motor means,said electric motor including a shaft extending therefrom, an inletbeing provided for said housing, an inlet cutter blade secured to saidshaft, grinder ring means including grinder teeth carried by saidhousing and encompassing said inlet cutter blade, an axial flow inducerimpeller positioned axially inwardly of and immediately adjacent saidinlet cutter blade, said impeller being secured to said shaft, acentrifugal pump means within said housing and including an impellersecured to said shaft, said pump having an inlet directly connecting toand receiving the discharge from said axial flow inducer impeller, and adischarge means for said pump means connecting thereto.

6. A grinder pump unit as in claim 5 where some of said grinder teeth onsaid grinder ring means are radially longer than others, and whereradially outwardly extending circular recesses are formed between saidgrinder teeth.

7. A grinder pump as in claim 5 where said grinder ring means has an oddnumber of teeth therein and every other one of said teeth is radiallyshorter than the teeth adjacent thereto, except for one pair of adjacentteeth which are of the same length.

8. A grinder pump unit as in claim 5 where said axial flow inducerimpeller has teeth thereon extending the axial length thereof and flatend surfaces are formed on said teeth to cooperate with end surfaces ofsaid grinder ring teeth for additional cutting and/or grinding action.

9. A grinder pump unit as in claim 1 where said motor is submersible.

10. A grinder pump unit as in claim 9 where said motor has two axiallyspaced seals with an oil chamber formed therein between said seals.

11. A grinder pump unit as in claim 1 where said axial flow inducerimpeller, which is of disc shape, has teeth thereon extending the axiallength thereof and end surfaces of said teeth are flat and said axialflow inducer impeller can be reversed for double use of said impellerwithout sharpening its teeth.

1. A grinder pump comprising an electric motor means including a shaftextending therefrom, an inlet being provided for said housing,cooperating cutter blade and grinder means members one of which issecured to said shaft at an inlet for the unit, an axial flow inducerimpeller positioned axially inwardly of and immediately adjacent saidcutter blade member, said impeller being secured to said shaft, and acentrifugal pump means including an impeller secured to said shaft, saidpump having an inlet directly connecting to and receiving the dischargefrom said axial flow inducer impeller.
 2. A grinder pump unit as inclaim 1 where teeth are provided on said grinder means and some teethare longer than others.
 3. A grinder pump as in claim 1 where saidgrinder means has an odd number of teeth therein and every other one ofsaid teeth is radially shorter than the teeth adjacent thereto, exceptfor one pair of adjacent teeth which are of the same length.
 4. Agrinder pump unit as in claim 1 where said axial flow inducer impellerhas teeth thereon extending the axial length thereof and surfaces ofsaid teeth cooperate with surfaces of said grinder teeth for additionalcutting and/or grinding action.
 5. A grinder pump unit comprising ahousing and electric motor means, said electric motor including a shaftextending therefrom, an inlet being provided for said housing, an inletcutter blade secured to said shaft, grinder ring means including grinderteeth carried by said housing and encompassing said inlet cutter blade,an axial flow inducer impeller positioned axially inwardly of andimmediately adjacent said inlet cutter blade, said impeller beingsecured to said shaft, a centrifugal pump means within said housing andincluding an impeller secured to said shaft, said pump having an inletdirectly connecting to and receiving the discharge from said axial flowinducer impeller, and a discharge means for said pump means connectingthereto.
 6. A grinder pump unit as in claim 5 where some of said grinderteeth on said grinder ring means are radially longer than others, andwhere radially outwardly extending circular recesses are formed betweensaid grinder teeth.
 7. A grinder pump as in claim 5 where said grinderring means has an odd number of teeth therein and every other one ofsaid teeth is radially shorter than the teeth adjacent thereto, exceptfor one pair of adjacent teeth which are of the same length.
 8. Agrinder pump unit as in claim 5 where said axial flow inducer impellerhas teeth thereon extending the axial length thereof and flat endsurfaces are formed on said teeth to cooperate with end surfaces of saidgrinder ring teeth for additional cutting and/or grinding action.
 9. Agrinder pump unit as in claim 1 where said motor is submersible.
 10. Agrinder pump unit as in claim 9 where said motor has two axially spacedseals with an oil chamber formed therein between said seals.
 11. Agrinder pump unit as in claim 1 where said axial flow inducer impeller,which is of disc shape, has teeth thereon extending the axial lengththereof and end surfaces of said teeth are flat and said axial flowinducer impeller can be reversed for double use of said impeller withoutsharpening its teeth.